Is it possible to add an auxiliary fuel tank behind cab？

I know of two OOs that added fuel capacity. Both just replaced their fuel tanks with used ones that would hold more fuel. This requires some body work but in my opinion, is the best overall solution. I think they had issues with syncing the fuel gauges with the fuel sender, but last I heard both worked out great. Considering just how heavy fuel is a gallon, I don't see a need to have more than 2 full 150-gallon tanks.

 

I agree with you about weight. I'm under permit when loaded so I can get away with more on the steer. I haul windmill blades. Approximately 240 overall and close to 15 feet wide.Very few truck stops we can go into. Fuel up before loading and come back with lighter tanks. Sometimes we do as bad as 3 mph in head winds. There are many time we have to sit under a load waiting on weather or permits.